ACROMEGALY DUE TO  A GH-SECRETING PITUITARY ADENOMA IN THE SPHENOID SINUS

G. Serra Soler*^a (Dr), JV. Gil Boix^a (Dr), M. Noval Font^a (Dr), M. Viñes Raczkowski^b (Dr), S. Tofé Povedano^a (Dr), A. Sanmartín Sánchez^a (Dr), I. Argüelles Jiménez^a (Dr)

^a Hospital Universitary Son Espases, Palma De Mallorca, SPAIN ; ^b Hospital Universitary Son Espases, Palma, SPAIN

* guillermo.serra@ssib.es

Introduction

Acromegaly is a rare, chronic disease characterized by an excess secretion of growth hormone (GH) and increased circulating insulin-like growth factor 1 (IGF-1) concentrations. 95% of cases harbour a GH-secreting pituitary adenoma. Less than 5 % of cases are due to an excess of GH releasing hormone (GHRH ) secretion from a hypothalamic tumor or a neuroendocrine tumour

Observations

A 54-year-old woman was admitted to the Urology department due to a nephritic colic complicated by septicaemia. Her medical records included type 2 diabetes mellitus treated with metformin and obesity. An endocrinologist was consulted due to poor diabetes control. Coarse facial features and large hands were observed, suspicious of an acromegaly. IGF-1 level was 406 ng/mL, with a glycated hemoglobin A1c (HbA1c) of 10.4%. She was discharged with insulin and metformin and had an appointment in two months. IGF-1 level was 711 ng/mL and HbA1c 7.8%. Oral glucose tolerance test was not done. Treatment was started with octreotide LAR 20 mg per month. A MRI of the brain showed an empty sella turcica with compression of the pituitary gland on the pituitary fossa. GHRH was normal and the octreoscan did not show lesions. Given the poor control of acromegaly, the dose of octreotide was increased and pegvisomant was added, without normalizing the IGF-1level. A new pituitary MRI was requested, which revealed an intrasphenoidal lesion on the right side greater than 1 cm in contact with the pituitary fossa. It was confirmed by a CT of the paranasal sinuses. An endoscopic transsphenoidal surgery was performed, noticing a tumour on the right side of the sphenoid sinus that infiltrated the clivus. The pathology report was compatible with a GH-secreting pituitary adenoma with Ki-67: 1% and p53 negative. After surgery, the IGF-1 level normalized

Discussion

- It is important to carefully evaluate structures surrounding the sella turcica when a pituitary adenoma is not initially found

- Adenomatous pituitary tissue within the sphenoid sinus can be explained by a pituitary tumor that protrudes inferiorly or more rarely, from pituitary embryological remnants located in the sphenoid sinus.

The author has declared no conflict of interest.